Buffing machine for flexible material such as leather

ABSTRACT

A BUFFING MACHINE FOR FLEXIBLE MATERIAL, SUCH AS LEATHER, HAVING ONE OR MORE BUFFING ROLLS OR ONE OR MORE ROLLS PROVIDING WITH BUFFING BELTS OR STRIPS, AT LEAST ONE REMOTE CONTROLLABLE COUNTER PRESSURE ROLL, AND A PLURALITY OF COUNTER PRESSURE ROLLS ARRANGED ON A CARRIER WITH A COUNTER PRESSURE ROLL WHICH IS DISPOSED OPPOSITE THE BUFFING ROLL COOPERATING WITH THE BUFFING ROLL AND BEING ADAPTED TO BE PUT INTO AN ADJUSTABLE WORKING POSITION OR DISPLACED OUT OF THE WORKING POSITION.

Oct. 5, 1971 c A DQRST 3,609,919

BJFJLAG MACHINE FOR FLEXIBLE MATERIAL SUCH AS LEATHER Filed Jan. 16, 1970 6 Sheets-Sheet 2 IN V EN TOR 0d. 5, 1971 c, VAN DORST 3,609,919

BUFFING MACHINE FOR FLEXIBLE MATERIAL SUCH AS LEATHER Filed Jan. 16, 1970 6 Sheets-Sheet 3 FIG.3

INVENTOR CORAIELIHS VRIV BURST Oct. 5, 1971 c VAN DQRST 3,609,919

BUFFING MACHINE FOR FLEXIBLE MATERIAL SUCH AS LEATHER Filed Jan. 16, 1970 6 Sheets-Sheet 4 FIG. 4

IN V EN TOR CORNELIUS vA/v boksT Oct. 5, 1971 c, VAN DORST 3,609,919

BUFFING MACHINE FOR FLEXIBLE MATERIAL SUCH AS LEATHER Filed Jan. 16, 1970 6 Sheets-Sheet 5 FIG. 5

'INVEN TOR aaRNKLHtS VAN IMRS'F BY g W11; 46% vii/ ,H'hrne Oct. 5, 1971 c N DORST 3,609,919

BJfi-LAG MACHINE FOR FLEXIBLE MATERIAL SUCH AS LEATHER Filed Jan. 16, 1970 6 Sheets-Sheet 6 L9 53 52 mi- 51 50 FIG. 6

IN V EN TOR coR/veLru 5 VAN 00/! ST United States Patent 3,609,919 BUFFLNG MACHINE FOR FLEXIBLE MATERIAL SUCH AS LEATHER Cornelius van Dorst, Rijen, Netherlands, assignor to Badische Maschinenfabrik G.m.b.I-I., Karlsruhe-Durlach, Germany Filed Jan. 16, 1970, Ser. No. 3,376 Claims priority, application Netherlands, Jan. 20, 1969, 6900944 Int. Cl. B24b 21/00 US. Cl. 51-439 Claims ABSTRACT OF THE DISCLOSURE A buffing machine for flexible material, such as leather, having one or more buffing rolls or one or more rolls providing with buffing belts or strips, at least one remote controllable counter pressure roll, and a plurality of counter pressure rolls arranged on a carrier with a counter pressure roll which is disposed opposite the buffing roll cooperating with the buffing roll and being adapted to be put into an adjustable working position or displaced out of the working position.

The invention relates to a buffing machine for flexible material, such as leather, and has particular application to a buffing machine having one or more bufling rolls or one or more rolls provided with buffing belts or strips, and also at least one remote-controllable, driven counterpressure roll.

The invention is based on the problem of how to provide a buffing machine wherein the counter-pressure roll may be replaced rapidly and easily by another counterpressure roll, for example if counter-pressure rolls made from rubber or the like are used these may be replaced by counter-pressure rolls having a different Shore hardness.

The invention provides a buffing machine of the abovediscussed type comprising a plurality of counter-pressure rolls arranged on a carrier, and a counter-pressure roll disposed opposite the buffing roll cooperating with it being adapted to be put into an adjustable working position or displaced out of the working position.

Since a plurality of counter-pressure rolls is arranged on a carrier, it becomes possible, by adjusting the carrier, to put any desired counter-pressure roll into the working position. The machine may also contain one or more buffing rolls or rolls having buffing strips or belts, so that one or more types of bufiing operations may be effected one after the other. In particular for the processing of leather, it is advantageous if two or more buffing rolls or two or more rolls having buffing strips, belts or bands are available, since leather must generally be subjected to two or more bufiing processes before the final treatment takes place. Preferably, a buffing roll or roller is not used, but there is employed a roll or roller having a buffing band or belt which then travels over a second roll and, on rotating the rolls, may be reciprocated transversely by the oscillation of the rolls. With the aid of an air flow or the like which, during reciprocation of the buffing belt, may be interrupted, it becomes possible to regulate the amplitude of the reciprocating movement.

In order to prevent the leather from being nonuniformly bufied, according to an advantageous arrangement of the invention the roll carrier, which is pivotal about a pivot extending parallel to the roll axes, is arranged to be adjustable via at least one arm on the frame of the ma chine, whereas the roll carrier is at the same time secured, through the agency of at least one eccentric, to the frame of the machine, with which said eccentric the roll carrier may be put into the working position and displaced out of the latter. Due to this design, wherein the counterice pressure roll may be anchored fast relatively to the machine, it becomes possible to avoid oscillations which would result in nonuniform surface quality and buffing marks which are clearly visible, even in the event of the thickness difference being extremely small.

The counter-pressure roll may, in the working position, be driven by an hydraulic motor. Since the counter-pressure roll, in order to achieve a buffing effect, is required to rotate more slowly, at constant velocity, than the bufiing roll, in devices of conventional design there has been used a retarding system comprising a worm which, however, has the disadvantage that a worm exhibits a certain degree of clearance or play relatively to the engaging gearwheel. Since the leather is, for varying reasons, in practice subjected to a variable buffing force, this is one of the causes of the above-mentioned nonuniform buffing effect. If a high buffing force is exerted, the buffing roll will, via the material, exert a corresponding force on the counterpressure roll in the direction of rotation. However, as soon as a smaller bufiing force is exerted, the pressure of the buffing roll on the material decreases, so that the force in the direction of rotation on the counter-pressure roll is smaller and may become smaller than the driving force. If, on the other hand, there is a clearance or play in the system the counter-pressure rotates nonuniformly, and this may result in buffing marks.

An embodiment of the invention will now be described by way of example with reference to the accompanying drawings. In the drawings:

FIG. 1 shows a lateral elevation of the example of embodiment of the bufling machine, in diagrammatic illustration;

FIG. 2 shows a section IIII according to FIG. 3;

FIG. 3 shows a section IIIIII according to FIG. 2;

FIG. 4 shows a rear elevational view of a portion of the machine, showing the drive device in diagrammatic manner;

FIG. 5 shows a vertical section through the coupling device;

FIG. 6 shows a lateral elevation with a partial section through the buffing machine.

As shown in FIGS. 1 to 3, the bufiing machine has a buffing roll or roller 1 over which travels a buffing belt or band 2 which is guided over a second roll (not shown) arranged in spaced relationship relative to the first roll. The second roll may be provided with a swivelling mechanism for reciprocating the bufiing belt in the transverse direction, this being important for releasing the swarf. The buffing roll may, however, also be differently designed and may for example be provided with a buffing coating. In this case, however, in order to release the swarf, the entire roll must be reciprocated in the transverse direction. In particular when using bufling belts, it is advisable to provide the buffing roll 1 with a coating or covering, for example of rubber in order to prevent the buffing belt 2 or the buffing coating from slipping.

Disposed under the buffing roll 1 is a carrier 3 carrying the counter-pressure rolls or rollers. The said carrier has three counter-pressure rollers 4 5 and 6 of which the roll 4 is shown in the working position. The carrier 3 is suspended twice from the machine frame 7, i.e. once in pivotal manner from a pivot 8 and, secondly, from a double eccentric 9 adjustably disposed on a pivot 10. (In each case one carrier 3 is secured on each side of the machine, so that it will suffice merely to discuss one carrier.) The double eccentric 9 consists of an eccentric disc 11 which may be displaced through approximately into two working positions, and also of an eccentric disc 12. In the case of the position shown in FIG. 1, the carrier 3 is disposed externally of the working position, whereas, on rotating the eccentric disc, it passes through approximately 180 into its working position. The stroke of the eccentric disc 11 is not quite 180, so as to avoid dead-centre positions. The eccentric disc 12 may be put into a plurality of positions, in this way taking into account varying diameters of the counter-pressure rolls. The eccentric disc 11 is preferably hydraulically adjustable, whereas the eccentric disc 12 is preferably manually adjustable. The eccentric 9 acts, via an arm 13, on pivot bearings 14 of carrier 3.

Arranged on the axis of the pivot bearings 14 is an eccentric 15 which is manually or (if so required) hydraulically adjustable, for the purpose of putting the carrier 3 into a coaxial or oblique position relative to the bufling roll. This may be important in particular in the case of leather, since the hide generally exhibits varying thicknesses which may result in the hide being non-uniformly buffed and the finishing agent subsequently applied on the leather not adhering at various points, thus producing a product which cannot be sold.

The pivot axis 8 has also an eccentric 16 by means of which the counter-pressure roll may be adjusted in the horizontal direction, so that the pivot 18 of the counterpressure roll may always be adjusted to a position where it is in alignment with the pivot 19 of the grinding roll 1 and the pivot 10 of the eccentric 9, independently of the diameter of the counter-pressure roll 4.

Thus, the carrier 3 has, in addition to a possibility for adjustment into and out of the working position, three adjustment possibilities for the counter-pressure roll. The carrier 3 has so many degrees of freedom so that the causes for nonuniform bufling effects may be eliminated. With the most stable design, the pivots 16 and 17 are preferably perpendicular to the pivots 10 and 18.

As may be seen from FIG. 3, the counter-pressure roll 4 is mounted in ball bearings 20 and 21 which are arranged in resilient linings 22 and 23. Thus, it is possible to compensate for a slight degree of play or clearance due to the differences in thickness in the material to be buffed.

From FIG. 3 it will furthermore be seen how the counter-pressure roll 4 may be removed out of the working position and replaced by the roll 5 or 6. For this purpose, there is provided a locking device adapted to be actuated with the aid of the shaft 17. The shaft 17, is, for this purpose, formed with a right-hand screwthr'ead at one end and with a left-hand screwthread at the other end. The threaded parts each cooperate with a cap 24, which, by means of a keybolt 25, is keyed in a sleeve 26 of a rflange 27 in which the counter-pressure rolls are mounted. Furthermore, a compression spring 29 is arranged between the inner side of the cap 24 and a shoulder 28 of the flange. The sleeve 26 is disposed in a sleeve 30 of a further flange 31 cooperating with a ring 32 which has an eye 33 formed with an aperture for fixing the arm 13 (FIG. 1). The cap 24 is provided with three pins 34 adapted to be put into operative connection with three apertures formed in the sleeve and corresponding to the working position of each one of the counter-pressure rolls.

By rotating the shaft 17, the two caps 24 are spaced apart until the pins 34 are released. Under the influence of the pressure of the springs 29, the pins 34 may be removed completely out of the flange 31 or the sleeve or bush 30. The spacing between the flanges 27 is meanwhile retained by a sleeve 35 surrounding the shaft 17. When the pins 34 are completely freed, the flanges 27 may be rotated, with the counter-pressure rolls mounted therein. When the correct position has been reached, the shaft 17 is rotated-back, whereby the pins 34 of the caps 24 penetrate into the corresponding apertures and lock the carrier 3. The rotation of the flanges 27 may be most simply effected with the aid of a gearing 55 driven by a shaft 56.

FIG. 3 shows the end of the shaft 18 of the counterpressure roll 4. To this end there may be secured a coupling or clutch device from which the counter-pressure roll may be driven. This device is shown in FIGS. 4 and 5 where a portion of the driven counter-pressure roll 4 with the shaft 18 is visible. Disposed in a housing 36 is the coupling or clutch device which is driven by an hydraulic motor 37 via a universal joint coupling 38. In order to make uncoupling possible, the universal joint shaft consists of two elements 3-9 and 40 which are fast in rotation and are adapted to be telescoped one within the other.

The universal joint shaft 38 (FIG. 5) acts on a shaft 41 which is aligned with the shaft 18 and at the end of which there is arranged a toothed clutch 42 co-operating with a gearwheel 43 at the end of the shaft 18. On decoupling, the element 39 of the universal joint clutch 38, the shaft 41 and the toothed clutch 4 2 are displaced (towards the right in the drawing), this being effected by means of a lifting motor 44. The piston 45 of the lifting motor is connected with bearings 46 for the shaft 41 and also with the housing 36 disposed in which is a ring 47 connected therewith and acting on a stop 48 secured on the shaft 41. If the piston 45 travels outwardly, it entrains the housing 36, the ring 47, the stop 48 and also the pivot 41, for the purpose of uncoupling.

The advantage of an hydraulic drive instead of a worm gearing has already been mentioned at the outset. Due to this coupling device, furthermore, one drive motor is sufficient. FIG. 6 shows a device with the aid of which the processed hide, emerging out of the gap or pass between the rolls 1 and 4, is prevented from adhering to the bufling roll and being entrained. For this purpose is provided a holdingdown means 49 taking the form of a plate contacting the bufiing roll 1 and preferably extends over the entire width of the roll 1. Since it is necessary to move the holdingdown means away from the roll 1, on replacing a bufling belt 2, there is provided furthermore a lifting motor 50 the piston 51 of which is connected with an extension 52 on a pusher or slide 53 on which the holding-down means 49 is secured. In order to be able to adjust the position of the holding-down means 49 relative to the roll 1, there is also an adjusting pin 54 by means of which the adjustment path of the pusher or slide member '53 may be limited. The piston 51 may be hydraulically or pneumatically actuated.

I claim:

1. In a device for the bufling of flexible material:

(a) at least one buffing roll,

(b) buffing guide means,

(c) at least one driven remote controllable counter pressure roll,

(d) a carrier and (e) a plurality of counter pressure rolls arranged on said carrier with one of said counter pressure rolls disposed opposite and co-operating with said buffing means and being adapted to be movable between a working position and an inoperative position.

2. In a device according to claim 1,

(a) a frame,

(b) pivot means parallel to the counter pressure roll secured on said frame,

(c) eccentric means and (d) at least one arm means, said carrier being pivotable about said pivot means for movement by at least one of said arm means and through the agency of said eccentric means for permitting the adjustment thereof into either of said working and inoperative positions.

3. Device according to claim 2, having an hydraulic motor for driving said counter pressure roll in said working position.

4. Device according to claim 3, having an hydraulically operated means interposed between said hydraulic motor and said driven counter pressure roll.

5. Device according to claim 4, wherein said buffing roll and said counter pressure roll when in said working position are disposed with their axes in alignment and said pivot means of said carrier and said carrier extend with their axes parallel to each other.

6. Device according to claim 1, comprising first and second eccentric means, said second eccentric means providing for adjusting a distance between said counter pressure roll disposed in the working position and said buffing roll.

7. Device according to claim 1, comprising locking means for fixing said counter pressure rolls in their said working position, said locking means comprising;

(a) two caps,

(b) pin means,

(c) a flange system defining apertures, said pin means co-operating with said apertures,

(d) extendable threaded elements for adjusting said counter pressure rolls and (e) means for pivoting the construction relatively to said flanges.

8. In a device according to claim 1, holding-down means in co-operation with the bufiing roll for preventing adhesion of the flexible material by said butfing roll and References Cited UNITED STATES PATENTS 8/1939 Jorgensen 5l78 1/1955 Sherrill et al 5l-l39 9/1964 'Schuster 51-139 WILLIAM R. ARMSTRONG, Primary Examiner US. Cl. X.R. 

